Self-retaining magazine plug

ABSTRACT

A self-retaining magazine plug insertable from the receiver end of the magazine tube of an autoloading shotgun. The plug has an elongated shank one of whose ends is bifurcated into complementary, resiliently-separated sections; the bifurcated sections include integral protuberances which increase the normal diameter of that end. The plug slides freely through an apertured spring follower until the protuberances are reached; intentional pressure against the follower forces the bifurcated portions together so the protuberances pass the aperture whereupon the portions expand to normally retain the plug in the magazine.

United States Patent [191 l lB Browning Oct. 21, 1975 1 1 SELF-RETAINING MAGAZINE PLUG 2511.505 6/1950 Hemmerling 42 4; A

y 2.635.378 4/1953 Pickney 4. 42 49 A [75] Invemor- Bmwmng, Ogden Utah 3,371,440 3/1968 Cassell t, 42/1 R Assignee: Browning Arms Company, Morgan,

Utah

Filed: Jan. 28, 1974 Appl. No: 437,172

Published under the Trial Voluntary Protest Program on January 28, 1975 as document no. B 437,172.

Foreign Application Priority Data Feb. 1, 1973 Canada 162609 US. Cl v r r r i v 42/49 A Int. Cl. F41C 25/08; F4lC 25/00 Field of Search 42/49 A, l R, l N, 49 R References Cited UNITED STATES PATENTS 10/1912 Lewis ,1 42/49 A 5/1913 Simpson i 4 i 42/49 A 12/1935 Russell et a1 42/49 A Primary ExaminerBenjamin A. Borchelt Assistant Examiner-C. T. Jordan Attorney, Agent, or FirmDavid V. Trask [57] ABSTRACT A self-retaining magazine plug insertable from the receiver end of the magazine tube of an autoloading shotgun, The plug has an elongated shank one of whose ends is bifurcated into complementary, resiliently separated sections; the bifurcated sections in clude integral protuberances which increase the normal diameter of that end. The plug slides freely through an apertured spring follower until the protu berances are reached; intentional pressure against the follower forces the bifurcated portions together so the protuberances pass the aperture whereupon the portions expand to normally retain the plug in the magazine.

7 Claims, 3 Drawing Figures SELF-RETAINING MAGAZINE PLUG BACKGROUND OF THE INVENTION 1. Field This invention relates to a magazine plug and a magazine assembly structured to accept the plug for use in repeating shotguns and, particularly, for use in repeating shotguns of the gas-operated type.

2. State of the Art block While the magazines of most repeating shotguns hold four or more cartridges, laws applicable to taking certain game require that the magazines be plugged to hold a lesser number of cartridges. For example, fed eral laws relating to the hunting of migratory birds allow a repeating shotgun to have no more than a threeround capacity. Common practice is to slip a wooden dowel of proper length into the magazine tube from its muzzle end to bleck a portion of the length of the tube.

The muzzle end of the magazine tube of most gasoperated autoloading shotguns contains mechanisms (such as a piston and obturator assembly) which are forced by the firing gases to activate reloading of the firearm. To insert a dowel from the muzzle end of such magazine tubes necessitates removal of the mecha nisms. Experience has shown that the removal and replacement of the mechansims is beyond the skill (or patience) of the typical sportsman; generally the firearm is taken to a skilled gunsmith who fits the plug into the magazine tube. In one known plugging arrangement, US. Pat. No. 2,511,505, a dowel-like plug is inserted into the magazine tube from the breech end after removal of the magazine tube from the receiver of the firearm.

SUMMARY OF THE INVENTION The invention provides a self-retaining magazine plug adapted to enter the receiver end of a magazine of an autoloading shotgun. The plug includes an elongated shank, one of whose ends is bifurcated into complementary, resiliently-separated sections; the bifurcated sections include integral protuberances which increase the normal diameter of that one end of the shank. A spring follower provided in the magazine has a central aperture dimensioned to admit the shank portion of the plug freely therethrough but to admit the end of increased diameter only when the halves of the bifur cated portion are pressed together. The follower is further adapted to press the bifurcated portions together upon intentional forcing of the bifurcated portions axially thereagainst.

BRIEF DESCRIPTION OF THE DRAWINGS The present invention may be more readily understood by referring to the following description and appended drawings, in which:

FIG. 1 is a sectional elevation of a magazine tube of an autoloading firearm illustrating the mechanism of the invention in place;

FIG. 2 is an exploded detail in perspective of the mechanism shown in FIG. 1; and

FIG. 3 is a sectional detail of the mechanism of FIG. 1 in another position.

DESCRIPTION OF THE PREFERRED EMBODIMENT In FIG. 1, a barrel ll of an autoloading shotgun is secured at one end to a receiver 12 wherein is housed the action of the firearm. A combined magazine tube and operating cylinder 13 (hereinafter referred to only as a magazine tube) is mounted below the barrel and like wise has one end secured to the receiver 12 to extend therefrom parallel to the barrel.

The breech or receiver end 13a ofthe magazine tube 13 houses a series of aligned shells 15 while the muzzle end 13b of the tube houses mechanisms (not shown] which drive shell-ejection mechanisms (not shown) in the breech of the gun. For example, a gas piston mechanism may be disposed in the muzzle end of the maga zine to be actuated by firing gases tapped from the bar rel. The shells in this type of firearm are conventionally loaded into the magazine tube one by one from below the lower front 16 of the receiver.

Between the gas piston (or like mechanism) and the shells is disposed a spring 17 and a spring follower 19. The helical spring 17 in FIG. 1 is slidably located in the magazine tube and has one end received into the spring follower 19 which is likewise slidable in the tube. The spring follower is a hollow cylindrical body with one closed end 19a which abuts the wad end 15a of the forwardmost shell 15 to effect a sliding partition between the end of the spring and the shell. The exterior of the rear end of the follower 19 may be flat or it may be rounded; e.g., hemispherical as shown. In any event, it has an aperture 21 formed therethrough and the interior surface of the end 190 is configurated to guide an interior plug 23 to the aperture as explained more fully hereinafter. The aperture is small enough to not interfere with cartridge loading nor to allow the coils of the spring 17 to escape therethrough. The function of the spring 17 and its follower 19 is conventional, as illustrated by US. Pat. Nos. 2,511,505 and 2,635,378. These patents describe similar spring arrangements, but with less specialized spring followers than that con templated by this invention.

According to this invention, a novel magazine plug is provided to cooperatively operate with the abovedescribed structure in the magazine tube. The magazine plug, generally designated 23 and best shown in FIG. 2, includes an elongated shank portion 24 of proper cartridge limiting length and of generally uniform cross section (whether cylindrical or otherwise) which fits easily through both the aperture 21 in the follower 19 and through the core of the spring 17. Near one end 230, the shank is enlarged and is bifurcated into complementary portions 25 and 26 by slot 27. The enlargement is due to smoothed lumps or protuberances 28 which are integrally formed on the respec tively bifurcated portions.

The overall diameter of the enlarged section of the plug 23 is such that while that section will not ordinarily pass through the aperture 21 in the follower, the portions 25 and 26 can be pressed together to slip the plug, lumps and all, through the aperture. In other words, the aperture 21 in the follower is small enough to contain spring 17 but large enough to admit the somewhat enlarged end of the plug 23. The plug is made ofa strong but resilient material (such as molded plastic) so that the bifurcated portion tends to return to its original diameter upon release after having been pinched together. As illustrated, the lumps 28 are formed somewhat back of the free ends 230 of the bifurcated portion of the plug to provide a leading tip of appropriate diameter to enter the aperture 21 of the spring follower l9.

Insertion and removal of the plug 23 is best understood by referring to both FIGS, 1 and 3. With the magazine empty of shells, the forward end 23b of the plug 23 can be aligned with and inserted through the aperture 21 in the follower 19. With a portion of the shank 24 through the aperture, a shell can be placed into the magazine and pressed against the bifurcated end of the plug. Due to the pressure, the tapered lumps 28 enter the aperture 21 and the bifurcated portions 26 and 27 are pressed together until the lumps are completely past the aperture. The shell 15 then bears directly on the spring follower l9, and the plug is generally in the self-retaining position shown in H6, l. The plug 23 checks the advance of the spring follower toward the muzzle end of the tube, and the magazine capacity is effectively limited.

To remove the plug 23, a hollow cylinder such as the empty shell 3] shown in FIG, 3 is inserted into the magazine tube and pressed against the spring follower 19', the inner surface of the end 19a of the follower l9 aids in guiding the bifurcated tip 23a of the plug into the aperture. With further pressure on the follower, the bifurcated portions 25, 26 are pinched towards one another and the enlarged lumps 28 of the plug slip past the follower 19 to the position shown in FIG. 3. The spring 17 urges the follower 19 to the breech end of the magazine tube 13 when the shells l5, 3] are removed. The plug is readily retrieved from the breech.

It is sometimes preferred that the taper of the lumps 28 be steeper on the side immediately adjacent the end 230 of the plug than on the opposite side so that a more forceful push is required to remove the plug than to insert it.

Reference herein to details of the preferred embodiment is not intended to restrict the scope of the claims which themselves recite those features regarded as essential to the invention.

I claim:

1. A self-retaining plug for insertion through an apertured spring follower into a magazine tube to limit the cartridge holding capacity of the magazine, said plug comprising a shank of reduced diameter for readily slidable insertion through the aperture in the spring follower and means integral with one end of said shank which retain that end of said shank from passing through the aperture except upon the application of substantial intentional pressure axially of said shank 2. A self-retaining magazine plug according to claim I, wherein said means includes said one end being bifurcated into substantially separated complementary portions and protuberances formed slightly back of the free ends of each of said complementary portions such that as said complementary portions are pressed to the aperture, said protuberances bear against the wall of the follower surrounding the aperture to pinch the complementary portions together to pass the aperture,

3. A self-retaining magazine plug according to claim 2, wherein said protuberances are smoothly tapered.

4. A self-retaining magazine plug according to claim 3, wherein said taper of said protuberances is slightly steeper on the side adjacent said free end than on the opposite side.

5. A self-retaining magazine plug according to claim 1, wherein said means includes said one end being bifurcated into resiliently separated complementary portions.

6. In a shotgun having a magazine tube, an improved magazine limiting assembly comprising:

a self-retaining piug member having a shank of reduced diameter and bifurcated, resiliently separated means which is integral with one end of the plug and which is of generally enlarged diameter when separated; and

a spring follower slidably arranged in the magazine tube, said follower having a concave inner end surface and an aperture formed generally concentrically therethrough, said aperture being dimensioned to allow said shank portion to be freely slidable therethrough but to admit said means of enlarged diameter only when the halves of said bifurcated portion are pressed together, said concave surface being adapted to press said halves together upon application of substantial intentional pressure axially on said shank.

7. In a repeating firearm having a tubular magazine;

a plug for limiting the cartridge holding capacity of the magazine and adapted to enter the magazine from the receiver end thereof, means integral with said plug for maintaining it in the magazine, and means provided in said magazine permitting the intentional removal of said plug from the receiver end of the magazine. 

1. A self-retaining plug for insertion through an apertured spring follower into a magazine tube to limit the cartridge holding capacity of the magazine, said plug comprising a shank of reduced diameter for readily slidable insertion through the aperture in the spring follower and means integral with one end of said shank which retain that end of said shank from passing through the aperture except upon the application of substantial intentional pressure axially of said shank.
 2. A self-retaining magazine plug according to claim 1, wherein said means includes said one end being bifurcated into substantially separated complementary portions and protuberances formed slightly back of the free ends of each of said complementary portions such that as said complementary portions are pressed to the aperture, said protuberances bear against the wall of the follower surrounding the aperture to pinch the complementary portions together to pass the aperture.
 3. A self-retaining magazine plug according to claim 2, wherein said protuberances are smoothly tapered.
 4. A self-retaining magazine plug according to claim 3, wherein said taper of said protuberances is slightly steeper on the side adjacent said free end than on the opposite side.
 5. A self-retaining magazine plug according to claim 1, wherein said means includes said one end being bifurcated into resiliently separated complementary portions.
 6. In a shotgun having a magazine tube, an improved magazine limiting assembly comprising: a self-retaining plug member having a shank of reduced diameter and bifurcated, resiliently separated means which is integral with one end of the plug and which is of generally enlarged diameter when separated; and a spring follower slidably arranged in the magazine tube, said follower having a concave inner end surface and an aperture formed generally concentrically therethrough, said aperture being dimensioned to allow said shank portion to be freely slidable therethrough but to admit said means of enlarged diameter only when the halves of said bifurcated portion are pressed together, said concave surface being adapted to press said halves together upon application of substantial intentional pressure axially on said shank.
 7. In a repeating firearm having a tubular magazine; a plug for liMiting the cartridge holding capacity of the magazine and adapted to enter the magazine from the receiver end thereof, means integral with said plug for maintaining it in the magazine, and means provided in said magazine permitting the intentional removal of said plug from the receiver end of the magazine. 